Process of extracting precious metals from their ores.



UNITED STATES PATENT "O FICE.

HENRY JOSHUA PHILLIPS, OF 'LONDON, ENGLAND. ASSIGNOR TO THE GOLDEN LINKCONSOLIDATED GOLD MINES, LIMITED, OF SAME PLACE.

PROCESS OF EXTRACTING PRECIOUS METALS FROM THEIR ORES.

SPECIFICATION forming part of Letters Patent No. 661,074, dated November6, 1900. Application filed July 31, 1899. Serial No. 725,683. (Nospecimens.)

T0 in whom it may concern:

Be it known that I, HENRY JOSHUA PHIL- LIPS, professor of chemistry, asubject of the Queen of Great Britain, residing at 123 Palace Chambers,Westminster, in the city of London, England, have invented a new orImproved Process of Extracting Precious Metals from Their Ores; and I dohereby declare the following to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in the art to whichit appertains to make and use the same.

This invention has for its objects new or improved process forextracting precious metals from their ores as. follows: The orecontaining the precious metals to be extracted is (without roasting)first reduced to an impalpable powder or finely-co'mminuted condition byany well-known or suitable means and is then subjected to the action of8,01 (known as dichlorid of sulfur, chlorid of sulfur, and monochloridof sulfur, all of which will hereinafter be referred to as chlorid ofsulfur) while heated (under heat and pressure) in a closed vessel,whereby the precious metals are converted into chlorids, which are thendissolved out in any suitable vessel by any suitable solvent andsubsequently separated into metallic form by any known or suitableprocess.

According to this invention the precious metals are extracted from theirores as follows: The ore in the finely-divided condition,

as aforesaid, is placed in a closed chamber or vessel of suitable sizeprovided with arms or stirrers adapted to stir up the contents of saidvessel (or said vessel may be arranged to revolve or otherwise arrangedto dispense with any such internal stirrers) and adapted to be heated inany suitable way. For instance, said vessel may be provided with ajacket surrounding or partly surrounding same, through which superheatedsteam can be passed, or said jacket may be adapted to contain oil, whichcan either be heated in a separate vessel and circulated through saidjacket, or said oil or other material contained in said jacket may beheated by a furnace, or direct heat may be applied to the exterior ofsaid vessel, which heated vessel is or may be provided with a valve orvalves, pressuregage, thermometer or them.

pyrometer, or any of The chlorid of sulfur (S 01 employed ac cording tothis invention before being mixed with the ore is first converted intofumes or vapors, (hereinafter referred to as vapor,) which may beeffected either in the vessel containing theme or in a separate vessel,and such vapor is brought into cont-act with the ore at such atemperature both of the vapor and ore in said vessel that saidchloridof-sulfur vapor is dissociated, and the chlosaid chlorids of theprecious metals thereby formed. If desired, however, the chlorid ofsulfur without being vaporized, as aforesaid, may be mixed direct withthe aforesaid ore in a vessel and then the temperature of same raiseilto such a point that chlorids will thereby be formed.

According to this invention the amount of chlorid of sulfur which is employed is proportioned according to the percentage of precious metal orprecious metals and substances in conjunction therewith or present inthe ore which will absorb chlorin under these conditions,-whichpercentage can be ascertained by assay or analysis sufficientlyaccurately for the purpose, and, furthermore, the temperture to whichthe ore and chlorid of sulfur are raised may be varied according to thestate of combination or otherwise of the precious metals in the ore.

Now according to thisinvention it has been discovered that chlorid ofsulfur when converted into fumes or vapor and applied to ore containingthe precious metals (in a finely- (livided condition) will at certaintemperature attack first of all the precious metals. For instance, in anore containing gold and carbonate of lime, &c., the sulfur-chlorid fumesor vapors will first of all only attack the gold, and this discoveryenables the amount of chlorid of sulfur to be employed to be exactlyascertained and used proportionately or according to the precious metalor metals known to be present in the ore. The temperature employed maybe about 210 centigrade for ordinary auriferous tellu ride ores; bu tany other suitable. temperature may be employed, according to thevarying natu re of the ores or as desired. Having thus ascertained theamount of chlorid of sulfur required for extracting the precious metalor metals from any given body of ore, the chlorid of sulfur may beintroduced into theaforesaid closed vessel containing such ore in theform of fumes or vapor,according to this invention, by placing thechlorid of sulfur in a separate vessel and therein subjecting it toheat, and thence the vapor is forced into the vessel containing the ore,or, if desired, said amount of chlorid of sulfur maybe mixed with theore or placed direct in the vessel containing said ore and the vesselthen closed and the temperature raised in the aforesaid manner and forthe aforesaid purposes,where by the precious metals are attacked by thechlorid of sulfur and chlorids of the precious metal or precious metalspresent are thus formed. Having thus formed these chlorids, it ispossible by raising the temperature still further to drive off thechlorin, thus leaving the precious metal or precious metals in ametallic state mixed with the ore, and same can then be extracted by anyknown meanssuch as concentrating, amalgamating, or (-y anidingprocess-or the precious metal or inetals can be recovered from saidchlorids in the manner first above described.

By the use herein of the term precious the gold and applied asaforesaid, but also an additional proportion of 5 01 isemployed,according to the amount of tellurium present in the ore andwhich it. is desired to recover, whereby the tellurinm can be extractedas well as the gold and separated therefrom.

Precious metal or precious metals can by this process be extracted fromrefractory or rebellious ores, or combined gold can thus be extracted,without the necessity of first roasting said ores.

Having now described my invention, what. I claim as new, and desire tosecure by Letters Patent of the United States, is-

1. Theherein-described process fol-extracting precious metals from theirores,wl1ich consists in subjecting said ores to the action of vaporizedchlorid of sulfur, substantially as described.

2. The process of extracting precious met als from their ores, whichconsists in pulverizing said ores and subjecting the same in a closedvessel under heat to the action of vaporized chlorid ofsulfur,substantially as described.

'lheherein-described process fol-extracting precious metals from theirores,whicl1 consists in pulverizing said ores, subjecting the same in aclosed vessel under heat to the action of chlorid of sulfur, the amountof chlorid of sulfur so employed being proportioned to the amount ofgold or other precious metals in the ore and which it is desired torecover, raising the temperature of the mixed ore and chlorid of sulfuruntil the latter is dissociated and chlorids of the precious metalsthereby formed and recovering the precious metal or metals from saidchlorids in any well-known manner, substantially as described.

In witness whereof I have hereunto set my hand in presence of twowitnesses.

HENRY JOSHUA PHILLIPS.

W'itnesses:

H. D. JAMESON, A. NUTTING.

